Long-Term Debt and Notes Payable - Summary of Long-Term Debt Obligations (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Long-term debt consists of:
Long-term borrowing	$ 891,547us-gaap_LongTermDebt	$ 88,562us-gaap_LongTermDebt
Less: Amounts due within one year	27,026us-gaap_DebtCurrent	39,543us-gaap_DebtCurrent
Total long-term debt	864,521	49,019
Senior Notes [Member]
Long-term debt consists of:
Long-term borrowing	500,000
Term Loan [Member]
Long-term debt consists of:
Long-term borrowing	298,500
Amortizing Notes [Member]
Long-term debt consists of:
Long-term borrowing	40,483
Capital lease obligation [Member]
Long-term debt consists of:
Long-term borrowing	2,802
Other financing [Member]
Long-term debt consists of:
Long-term borrowing	743
North Ocean 105 [Member]
Long-term debt consists of:
Long-term borrowing	49,019	57,189
North Ocean 102 [Member]
Long-term debt consists of:
Long-term borrowing		$ 31,373

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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